<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .heart {
      width: 100px;
      height: 100px;
      position: relative;
      margin-left: 50px;
    }
    .heart:before, .heart:after {
        position: absolute;
        width:50%;
        height: 100%;
        content: "";
        display: inline-block;
        background: red;
        transform: rotateZ(45deg);
        transform-origin: 0 100%;
        border-radius: 25px 25px 0 0;
        left: 0;
      }
      .heart:before{
        left: 20%;
        transform: rotateZ(-45deg);
        transform-origin: 100% 100%;
      }
  </style>
</head>
<body>
  <!-- [css] 用CSS绘制一个红色的爱心 -->
  <div class="heart"></div>
</body>


</html>